I cant attach object to armature
The Transfer Weight function has some parameters (the values are not visible in your video).

By default, i have these parameters :



For you want to do, try this one for the source layer selection :



That will allow to create groups with the same names you have in the character model.

If this still dont work correctly, try to change the vertext mapping and the ray radius value (as your two meshes does not fit exactly) :



Anyway you'll probably need to try values and adjust them so that is corresponds to what you want.